Black Smoke & Power Loss: CrosslandX Boost Pressure Issue?

Hey! I had pretty much the same symptoms with my 2016 Vauxhall Mokka diesel. I have some experience working on cars, but turbo issues are best left to professionals. That whistling and black smoke were exactly what I dealt with, turned out to be a faulty waste gate valve. Took it to my trusted workshop, and they confirmed the diagnosis. The repair, including parts and labor, set me back about €860. Since then, the car's been running like new. What's your mileage and maintenance history? Just to be sure we're dealing with the same issue. If it helps, let me know the specific engine variant you've got in your CrosslandX.

Thanks for sharing your experience! Mine's at 207151 KM now, and I just had it serviced last month. That's interesting about the waste gate valve, the symptoms do sound identical to what I'm experiencing. Did your mechanic mention any early warning signs I should've watched out for? I might give Dave's Auto Service a try since they sorted yours out well. €860 isn't cheap but beats having bigger issues down the line!

Hey again! Yeah, those symptoms you mentioned are definitely similar to what I experienced with my Mokka. Looking back, there were some early signs I probably should've mentioned earlier, I noticed a slight drop in fuel efficiency about a month before the major symptoms started, and occasionally the boost would feel inconsistent even during normal driving. Dave's team did explain that these issues often start small and get worse over time. In my case, they said the waste gate was gradually degrading, which explains why the problems got more noticeable over time. With your mileage being around 207K, it's definitely in the range where these things can happen. One thing I forgot to mention, before I took it to Dave's, I tried cleaning the boost pressure sensor thinking it might be a cheaper fix, but that didn't help at all. Dave actually showed me the old waste gate after they replaced it, and you could clearly see the wear and tear. If you do take it to Dave's, ask for Mike, he's the turbo specialist there and really knows his stuff. He'll probably want to do a proper diagnostic first, but based on what you're describing, I'd bet you're looking at the same issue I had. Let me know how it goes!

Thanks so much for all the detailed info! That's super helpful to know about the fuel efficiency drop being an early warning sign, now that you mention it, I did notice I was filling up more frequently lately but didn't connect the dots. I'll definitely check out Dave's and ask for Mike. Really appreciate you taking the time to explain everything, especially about the boost pressure sensor, saves me from going down that rabbit hole! I'll give them a call tomorrow and book it in. Will let you know how it turns out, but feeling much more confident about getting this sorted now. Thanks again for all your help!